A report out today says profits at Stella McCartney's company increased sixfold last year. Clearly, her feel-good formula is working, and all the elements were in place at her Spring show: the best soundtrack in Paris (this time including a song from papa, Sir Paul), an arty backdrop (inspired by coloring books and designed by the British artists Dinos and Jake Chapman), and clothes with her trademark mix of effortlessness and sex appeal.

She started by tweaking her beloved jumpsuits. They came tailored in makeup pink, with deep lapels that plunged to the navel. McCartney's kind of slouchy, slightly oversize tailoring has caught on in a major way: The longer boyfriend jacket with the strong shoulder and the pushed-up sleeve that she showed today over little cocktail dresses or with cropped pants has become a big trend. Her trench coveralls might not be adopted as readily—we don't all have legs like Natasha Poly's.

But the collection's sexy side came across in plenty of other, more real-world ways. Dévoré sweaters played a demure game of peekaboo, while silk dresses in steely gray took a provocative dip in back. For evening, she kept the silhouette short, sharp, and graphic in black and white. Simply put, she's got cool-girl style down to a science.